Flat heat pipe structure

ABSTRACT

A flat heat pipe structure includes a flat pipe, a radial capillary structure and an axial capillary structure. The pipe has a containing space for sealing and storing a working fluid, and the pipe is formed by two opposite bottom walls and two sidewalls laterally and respectively disposed on the two bottom walls, and the pipe further has an evaporation portion, and the radial capillary structure is situated in the evaporation portion and radially surrounded and attached onto the two bottom walls and two sidewalls, and the axial capillary structure is extended in a lengthwise direction of the pipe, disposed in the containing space, and attached onto one of the sidewalls, and the axial capillary structure is extended to the evaporation portion of the pipe and coupled to the radial capillary structure.

FIELD OF THE INVENTION

The present invention generally relates to heat conducting components, in particular to a flat heat pipe with a capillary structure.

BACKGROUND OF THE INVENTION

Heat pipe is a heat conducting component that achieves a quick heat dissipation effect by means of a change of liquid and vapor phases and generally comes with an evaporation portion at an end of the heat pipe and a condensation portion at another end of the heat pipe to produce a temperature difference. If the evaporation portion receives heat, a working fluid in the evaporation portion can be vaporized quickly due to the vacuum condition inside the heat pipe, and the heat can be conducted to the condensation portion having a lower temperature through the heat pipe. Now, the heat at the condensation portion can be dissipated from an external heat dissipating component (such as a heat dissipating fin), so that the vaporized working fluid can resume its original liquid phase and return to the evaporation portion through a capillary structure disposed on an internal wall of the heat pipe, and the cycle can be repeated to achieve the effect of conducting heat.

To minimize the occupying space and meet the desired thin and compact design requirements of an electronic product, the heat pipe is designed in a flat shape. However, the space in the flat heat pipe becomes much smaller after the heat pipe is pressed, and the space is just large enough for installing the capillary structure and related supporting components only. When the working fluid is heated at the evaporation portion and changed into a vapor phase, the reduced space in the heat pipe may cause difficulties for the working fluid to conduct heat to the condensation portion.

In view of the foregoing shortcomings of the conventional flat heat pipe structure, the inventor of the present invention based on years of experience in the related industry to conduct extensive researches and experiments, and finally designed and developed a feasible flat heat pipe structure to overcome the shortcomings of the prior art.

SUMMARY OF THE INVENTION

Therefore, it is a primary objective of the present invention to provide a flat heat pipe structure that makes use of the installation relation of radial and axial capillary structures to reserve sufficient space for a heat conduction path of a vaporized working fluid inside a heat pipe, so as to avoid any possible hindrance to the change of vapor and liquid phases of a working fluid.

To achieve the foregoing objectives, the present invention discloses a flat heat pipe structure comprising a flat pipe, a radial capillary structure, and an axial capillary structure, wherein the pipe has a flat containing space for sealing and storing a working fluid, and the pipe is formed by two opposite bottom walls and two sidewalls laterally and respectively disposed on the two bottom walls and provided for enclosing and defining the containing space, and the pipe further has an evaporation portion, and the radial capillary structure is situated in the evaporation portion, and radially surrounded and attached onto the two bottom walls and the two sidewalls, and the axial capillary structure is extended in a lengthwise direction of the pipe, installed in the containing space, and attached onto one of the sidewalls, and the axial capillary structure is extended to the evaporation portion of the pipe and coupled to the radial capillary structure.

To make it easier for the examiner to understand the objects, characteristics and effects of this invention, we use preferred embodiments together with the attached drawings for the detailed description of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view of a preferred embodiment of the present invention;

FIG. 2 is a perspective view a preferred embodiment of the present invention;

FIG. 3 is a cross-sectional view of FIG. 2;

FIG. 4 is a schematic view of an application of a preferred embodiment of the present invention; and

FIG. 5 is a cross-sectional view of another preferred embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The technical characteristics and contents of the present invention will become apparent with the following detailed description accompanied with related drawings. The drawings are provided for the purpose of illustrating the present invention only, but not intended for limiting the scope of the invention.

With reference to FIGS. 1 and 2 for an exploded view and a perspective view of a flat heat pipe structure in accordance with a preferred embodiment of the present invention respectively, the flat heat pipe structure has a heat pipe 1 comprising a flat pipe 10, a radial capillary structure 11, and an axial capillary structure 12.

The pipe 10 also has a flat containing space 100 therein, and the pipe 10 is formed by two opposite bottom walls 101 and two sidewalls 102 laterally and respectively disposed on the two bottom walls 101 and provided for enclosing and defining the containing space 100. The radial and axial capillary structures 11, 12 are attached onto an internal wall of the containing space 100 of the pipe 10, and an appropriate quantity of working fluid (not shown in the figure) is sealed and stored in the pipe 10. The pipe 10 includes an evaporation portion 103 disposed at any end (or a distal end), or in the middle section of the pipe 10. Of course, the pipe 10 may have a plurality of evaporation portions 103 as well.

The radial capillary structure 11 is situated in the evaporation portion 103 of the pipe 10, and radially surrounded and attached onto the two bottom walls 101 and the two sidewalls 102. The radial capillary structure 11 can be made of a metal mesh or a sintered powder.

In FIG. 3, the axial capillary structure 12 is extended along a lengthwise direction of the pipe 10, installed in the containing space 100, and attached onto one of the sidewalls 102. When the axial capillary structure 12 is extended to the evaporation portion 103 of the pipe 10, the axial capillary structure 12 is stacked and integrated with the radial capillary structure 11 for facilitating the sealing and storage of the working fluid in the pipe 10, such that the working fluid can flow smoothly between the radial and axial capillary structures 11, 12. The axial capillary structure 12 can be a strip-shaped fiber bundle, a metal mesh rolled into a strip-shape or a powder sintered into a strip shape, or a ditch formed on one of the sidewalls 102.

With the aforementioned structure, the flat heat pipe structure in accordance with the present invention can be achieved.

In FIG. 4, the evaporation portion 103 of the heat pipe 1 is in contact with a heat source 2, and an end of the heat pipe 1 away from the evaporation portion 103 includes a plurality of heat dissipating fins 3 connected with one another. When the heat source 2 generates heat and the working fluid in the radial capillary structure 11 of the heat pipe 1 starts vaporizing, the vaporized working fluid conducts heat to each heat dissipating fin 3 through the containing space 100 since the radial capillary structure 11 is situated on the evaporation portion 103 only. After the condensation effect of each heat dissipating fin 3 take place to resume the working fluid into a liquid state, the axial capillary structure 12 is provided for returning the working fluid in the liquid state to the evaporation portion 103. Even though the containing space in the flat heat pipe is relatively small and narrow, the installation relation of the radial and axial capillary structures 11, 12 can avoid a possible situation of the vaporized working fluid and the liquid-phase working fluid from flowing towards each other, so as to facilitate a smooth cycle of the change of liquid and vapor phases of the working fluid in the heat pipe 1.

With reference to FIG. 5 for a cross-sectional view of a flat heat pipe structure in accordance with another preferred embodiment of the present invention, the axial capillary structure 12 is extended to an end of the heat pipe away from the evaporation portion 13, and the flat heat pipe structure further includes a coupling section 120 attached onto a distal surface of the pipe 10 of the heat pipe 1, such that the backflow of working fluid in the liquid state can be conducted along the coupling section 120 and attached by the axial capillary structure 12 to facilitate the backflow of the working fluid in the liquid state.

In summation of the description above, the present invention improves over the prior art and complies with the patent application requirements, and thus is duly filed for patent application. While the invention has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims. 

1. A flat heat pipe structure, comprising: a flat pipe, including a flat containing space formed therein, and containing a working fluid, and the pipe being formed by two opposite bottom walls and two sidewalls laterally and respectively disposed on the two bottom walls, and provided for enclosing and defining the containing space, and the pipe further having an evaporation portion; a radial capillary structure, disposed in the evaporation portion of the pipe, and radially surrounded and attached onto the two bottom walls and the two sidewalls; and an axial capillary structure, extended along a lengthwise direction of the pipe, disposed in the containing space, and attached onto one of the sidewalls, and the axial capillary structure being extended to the evaporation portion of the pipe and coupled to the radial capillary structure.
 2. The flat heat pipe structure of claim 1, wherein the evaporation portion of the pipe is situated at an end of the pipe.
 3. The flat heat pipe structure of claim 1, wherein the evaporation portion of the pipe is situated at a middle section of the pipe.
 4. The flat heat pipe structure of claim 1, wherein the evaporation portion of the pipe comes with a plurality, and the evaporation portions are situated at any end or a middle section of the pipe.
 5. The flat heat pipe structure of claim 1, wherein the radial capillary structure is a metal mesh.
 6. The flat heat pipe structure of claim 1, wherein the radial capillary structure is made of a sintered powder.
 7. The flat heat pipe structure of claim 1, wherein the axial capillary structure is a strip-shaped fiber bundle.
 8. The flat heat pipe structure of claim 1, wherein the axial capillary structure is formed by rolling a metal mesh into a strip shape.
 9. The flat heat pipe structure of claim 1, wherein the axial capillary structure is a powder sintered into a strip shape.
 10. The flat heat pipe structure of claim 1, wherein the axial capillary structure is a ditch formed on one of the sidewalls.
 11. The flat heat pipe structure of claim 1, wherein the axial capillary structure further includes a coupling section extended from the axial capillary structure and attached onto a distal surface of the pipe. 